Their normal migration route tends to cut through southern Illinois. But for some reason, Bumgardner says, they've shifted a bit east. They're coming from winter homes along the Gulf Coast and going to summer grounds between Wisconsin and the Dakotas and central Canada, the naturalists say.

This is the peak time to see the pelicans, but they could continue to migrate throughout April, Cassady says.

Just don't expect any group of the pelicans to linger more than a few days.

'Tis the season, Cordell says. Lots of migrant birds are passing through Potato Creek, he says, and the ospreys are back to their nests in the park for the warm months.